Cyclic urea derivatives and process for their manufacture

ABSTRACT

Novel cyclic urea derivatives containing silicon atoms have the general formula   WHEREIN R is a hydrocarbon radical optionally being interrupted by oxygen atoms in ether linkages, R&#39;&#39; and R&#39;&#39;&#39;&#39; (same or different) are hydrocarbon radicals, halohydrocaron radicals, cyanohydrocarbon radicals, or alkoxy radicals, and R&#39;&#39;&#39;&#39;&#39;&#39; is a hydrocarbon radical.

United States Patent Giilitz et a1;

[451 Apr. 3, 1973 [73] Assignee: Farbeniabriken 221 Filed; Oct.'16,1970

21 Appl.No.: 81,515

I [30] Foreign Application Priority Data Oct. 29, 1969 Germany ..P 19 54 447.9

[52] US. Cl ..260/448.8 R, 117/123 C, 260/465 E [51] Int. Cl. ..C07f 7/18, C07d 103/04 [58] Field of Search .....260/448 .8 R

[56] References Cited UNITED STATES PATENTS 3,436,415 4/1969 Finkbeiner 260/448.8 R X 3,436,416 4/1969 Finkbeiner et a1. ..260/448.8 R X Primary Examiner-Daniel E. Wyman Assistant Examiner-P. F Shaver Attorney-Burgess, Dinklage & Sprung 57 ABSTRACT Novel-cyclic urea derivatives containing silicon atoms have the general formula 3 HzO-Si-R RN N-R wherein R is a hydrocarbon radical optionally being interrupted by oxygen atoms in ether linkages, R and 'R'{ (same or different) are hydrocarbon radicals,

'halohydrocaro'n radicals, cyanohydrocarbon radicals, I or alkoxy radicals, and R' is a hydrocarbon radical.

13 Claims, No Drawings CYCLIC UREA DERIVATIVES AND PROCESS FOR THEIR MANUFACTURE These 2,5-diaza-3-silacyclopentanones can be produced, according to the invention, by reacting an aminomethylalkoxy-silane of the general formula llkll :C-SiR R-N N-R- (R', R" and R as above; X alkyl) at a temperature between and 250C with an isocyanate of the general formula RNCO (R as above) and recovering the product by distillation under reduced pressure.

These products are suitable for promoting the adhesion of synthetic resins to siliceous surfaces, for use as intermediates for organopolysiloxane resins, and for use as cross-linking agents in water-reactive organopolysiloxane preparations.

The present invention. relates to new cyclic urea derivatives containing silicon atoms, which derivatives are suitablefor strengthening the adhesion of synthetic resins -to silicieous surfaces when used as an intermediate layer, for use as intermediates in the manufacture of organopolysiloxane resins, and for use as crosslinking agents in organopolysiloxane compositions which can be converted into elastomers atroom temperature by reaction with water.

These new urea derivatives are 2,5-diaza-3-silacyclopentanones of the general formula H1c.-s1-R' R"'N R according to the invention, by. reacting an aminomethylalkoxysilane of the general formula v R R"'-NH-cH, s i-R'.

wherein R, R and R"" are as above and X is an alkyl radical having one to four carbon atoms, at a temperature between 0 and 250C, if necessary with initial cooling and subsequent heating, with an equimolar amount or a slight excess (for example 10 percent) of an isocyanate of the general formula RNCO, wherein R is as above, and isolating the reaction products by fractional distillation unde reduced pressure.

The aminomethylalkoxysilanes to be used in the above process may be obtained according to known methods, for example by reaction of I a halogenomethylalkoxysilane with a primary amine. The entire process then takes place in accordance with the following reaction scheme:

Surprisingly, the alkoxysilylmethylureas which are formed first (approximately inthe temperature range 0 to 130C) in accordance with the known method of an isocyanate addition, cyclize at a moderately elevated temperature, as a rule between 30 and 250C, with elimination of alcohol. The subsequent distillation of the reaction mixture, which should as a rule be can ried out at-a pressure of between 0.01 and 100 mm of mercury, completes the process and furnishes the heterocyclic compounds according to the invention as mostly colorless, liquid distillates of pleasant odor, in a yield of between 60 and 95 percent. The Si-N and SiO bonds of these compounds can easily be split by hydrolysis.

he following-Examples are given for the purpose of illustrating the invention.

EXAMPLE 1 61g. (0.49 mol) cyclohexyl isocyanate are added dropwise to g. (0.49 mol) methyl- (methylaminomethyl)-di-ethoxysilane, with exclusion of moisture and whilst stirring, the temperature being kept at between 15- and 30C'by external cooling with ice. Thereafter the reaction mixture is distilled under reduced pressure and a colorless liquid of refractive index n 1.4870 is obtained as a fraction which passes over at 0.65 mm of mercury between and 142C. This product has the structural formula (EH: Si-0 C2H5 EXAMPLE 2 19.8 g. (0.166 mol) phenyl isocyanate are added to 41 g. (0.166 mol) methyl-(n-butylaminomethyU- diisopropoxysilane in the manner described in Example 1. The crystalline product first obtained hereby is distilled after fusing under reduced pressure, and at 0.4 mm of mercury and 154C a liquid fraction is obtained, having a refractive index of n 1.5170 and a structure in accordance with the formula (3H3 glo s-0011mm).

EXAMPLE 3 49 g. (0.2 mol) methyl-(cyclohexylaminomethyl)-diethoxysilane are reacted with 17.4 g. (0.2 mol) methoxymethyl isocyanate analogously to the preceding Examples, and on distillation a liquid fraction which passes over between 143 and 145C at 0.6 mm of mercury is obtained, having a refractive index m, 1.4815 and a structure of formula 50 g. (0.4 mol) cyclohexyl isocyanate are added dropwise to 100 g. (0.364 mol) (cyclohexylaminomethyl)-triethoxysilane, with exclusion of moisture and whilst stirring, with the temperature being allowed to rise to 60C. Distillation at 0.01 mm of mercury between 183 and 190C yields a liquid fraction having a refractive index of n 1.4912 and a structure in accordance with the formula IIZ CHi- O C2115 II IL' II ll 0 EXAMPLE 5 EXAMPLE 6 50 g. (0.4 mol) cyclohexyl isocyanate are added dropwise to 86 g. (0.4 mol) dimethyl-(cyclohexylaminomethyl)-ethoxysilane at temperatures between 0 and 20C, analogously to Example 1. Subsequent distillation at 0.07 mm of mercury between and C yields a fraction which solidifies on cooling, having a melting point of 147C and a structure in accordance with the formula EXAMPLE 7 98 g. (0.4 mol) methyl-(cyclohexylaminomethyl)-diethoxysilane are reacted with 50 g. (0.4 mol) cyclohexyl isocyanate analogously to the preceding Example, and on subsequent distillation a fraction which passes over at 0.07 mm of mercury between 167 and 170C and which solidifies on cooling is obtained. This product melts between 65 and 68C, and has the structural formula $131 1120 SlOCzH5 H i if g EXAMPLE8 17.4 g. (0.147 mol) phenyl isocyanate are added dropwise to 30 g. (0.147 mol) methyl- (methylaminomethyl)-di-isopropoxysilaneanalogously to Example 1, at temperatures between 20 and 30C. Subsequent distillation yields, at a pressure of between 0.9 and 1 mm of mercury, a liquid fraction which passes over between 157 and C, having a refractive index of n,,= 1.5923 and a structure formula EXAMPLE 9 49.5 g. triethoxysilane are reacted with 10.3 g. (0.18 mol) methyl-isocyanate analogously to the preceding Example; Subsequent distillation yields, at a pressure of between 0.6 and 1 mm of mercury, a liquid fraction which passes over between 161 and 165C having a refractive index of n 1.4735 and a structure of formula (cyclohexylaminomethyh- EXAMPLE l0 33.2 g. (0.4 mol) allyl isocyanate are added to 100 g.

having a refractive index of m, 1.4820 and a structure according to the formula EXAMPLE 11 62.5 g. (0.5 mol) cyclohexyl isocyanate are admixed with 134.5 g. (0.5 mol) (phenylaminomethyl)-triethoxysilane whilst stirring and excluding moisture, at a temperature which is initially kept at between and C. Thereafter the reaction mixture is heated to 120C for 4 hours and is subsequently distilled. Hereupon a fraction is obtained in the pressure range of 0.6 to 1 mm of mercury between l80and-192C, which has a structure of formula EXAMPLE 12 the ' formula What is claimed is:

l. 2,5-Diaza-3-silacyclopentanones of the general formula 0 ll wherein R is a monovalent radical having up to 15 carbon atoms selected from the group consisting of alltyl,

cycloalkyl, alkenyl, aromatic hydrocarbon radicals and ethers composed of carbon, hydrogen and oxygen,

R and R are each monovalent radicals selected from the group consisting of alkoxy radicals havin one to four carbon atoms, and

R is a hydrocarbon radical having up to 10 carbon atoms selected from the group consisting of saturated aliphatic, cycloaliphatic, olefinic and aromatic hydrocarbon radicals. I

2. Process for the manufacture of a 2,5-diaza-3-sila-.

cyclopentanone according toclaim 1 which comprises reacting an amino-methylalkoxysilane of the general R R -NH-om-si-R' wherein X is an alkyl radical having one to four carbon atoms, with slight a molar excess of an isocyanate of the general formula RNCO, at a temperature between 0 and 250C, and isolating the reaction products by fractional distillation under reduced pressure.

3. Process according tov claim 2, wherein the reactants are initially cooled and are subsequently heated.

4. Process according to claim 2 wherein the isocyanate is used in an excess of up to 10 mole per cent.

5. Process according to claim 2 wherein the fractional distillation is carried out at a pressure of 0.01 to mm of mercury.

6. 1 2,5-Dicyclohexyl-3,3-diethoxy-2,5-diaza 3-silacyclopentanone. I

7. 2-Phenyl-3,3-diethoxy-5-cyclohexyl-2,5-diaza-3- silacyclopentanone.

8. 2-Methyl-3,3-diethoxy-5-cyclohexyl-2,5-diaza-3- silacyclopentanone.

9. 2-Allyl-3,3-diethox'y-5-cyclohexyl-2,5-diaza-3- silacyclopentanone. 1

10. 2-Cyclohexyl-3,3-diethoxy-5-phenyl-2,5-diaza-3- silacyclopentanone.

11. A compound as claimed in claim 1 wherein R and R are both ethoxy.

12. A compound as claimed in claim 11 wherein R is a member selected from a group consisting of cyclohexyl and phenyl.;

13. A compound as claimed in claim 12 wherein R is a member of a group consisting of methyl, cyclohexyl, allyl and phenyl. 

2. Process for the manufacture of a 2,5-diaza-3-silacyclopentanone according to claim 1 which comprises reacting an amino-methylalkoxysilane of the general formula
 3. Process according to claim 2, wherein the reactants are initially cooled and are subsequently heated.
 4. Process according to claim 2 wherein the isocyanate is used in an excess of up to 10 mole per cent.
 5. Process according to claim 2 wherein the fractional distillation is carried out at a pressure of 0.01 to 100 mm of mercury.
 6. 2,5-Dicyclohexyl-3,3-diethoxy-2,5-diaza-3-silacyclopentanone.
 7. 2-Phenyl-3,3-diethoxy-5-cyclohexyl-2,5-diaza-3-silacyclopentanone.
 8. 2-Methyl-3,3-diethoxy-5-cyclohexyl-2,5-diaza-3-silacyclopentanone.
 9. 2-Allyl-3,3-diethoxy-5-cyclohexyl-2,5-diaza-3-silacyclopentanone.
 10. 2-Cyclohexyl-3,3-diethoxy-5-phenyl-2,5-diaza-3-silacyclopentanone.
 11. A compound as claimed in claim 1 wherein R'' and R'''' are both ethoxy.
 12. A compound as claimed in claim 11 wherein R'''''' is a member selected from a group consisting of cyclohexyl and phenyl.
 13. A compound as claimed in claim 12 wherein R is a member of a group consisting of methyl, cyclohexyl, allyl and phenyl. 